Mounting means for cutter bits

ABSTRACT

Mounting means for cutting tools of the type having an elongated shank of circular cross section, a hard cutting tip at one end and an abutment surface at the other end. The mounting means comprises a body having a forward surface, a rearward surface and a shank receiving perforation extending through the body from the forward surface to the rearward surface. The shank receiving perforation is of such diameter as to permit free rotation of the cutting tool shank therein, and is of such length that the abutment end of the cutting tool shank extends beyond the rear surface of the body. The body is mounted on a driven element of a mining machine. An abutment means is provided in association with the driven element, the abutment means presenting an abutment surface cooperating with the abutment surface on the cutting tool shank and spaced from the rear surface of the mounting means body.

United States Patent [72] Inventor Claude B. Krekeler Cincinnati, Ohio [21] Appl. No. 2,874 [22] Filed Jan. 14, 1970 [45] Patented Dec. 14, 1971 [73] Assignee The Cincinnati Mine Machinery Company Cincinnati, Ohio [54] MOUNTING MEANS FOR CUTTER BITS 6 Claims, 6 Drawing Figs.

[52] US. Cl 299/86, 299/92 [51] Int. Cl E2lc 25/46 [50} Field of Search 299/86, 92

[56] References Cited UNITED STATES PATENTS 3,331,637 7/1967 Krekeler 299/92 3,397,012 8/1968 Krekeler.... 299/86 3,397,013 8/1968 Krekeler 299/86 Primary Examiner-Ernest R. Purser Attorney-Melville, Strasser, Foster & Hoffman ABSTRACT: Mounting means for cutting tools of the type having an elongated shank of circular cross section, a hard cutting tip at one end and an abutment surface at the other end. The mounting means comprises a body having a forward surface, a rearward surface and a shank receiving perforation extending through the body from the forward surface to the rearward surface. The shank receiving perforation is of such diameter as to permit free rotation of the cutting tool shank therein, and is of such length that the abutment end of the cutting tool shank extends beyond the rear surface of the body. The body is mounted on a driven element of a mining machine. An abutment means is provided in association with the driven element, the abutment means presenting an abutment surface cooperating with the abutment surface on the cutting tool shank and spaced from the rear surface of the mounting means body.

MOUNTING MEANS FOR CUTTER BITS BACKGROUND OF THE INVENTION l. Field of the invention The invention relates to improved means for mounting cutting tools on the driven elements of mining machines and the like, and more particularly to improve means for mounting cutting tools of the type having an elongated shank of circular cross section with a cutting means at one end and an abutment surface at the other end. 7

2. Description of the Prior Art Recently, extensive use has been made of pick-type bits on mining machines and the like. Such cutter bits are of two general types. In one type, the cutter bit comprises an elongated shank having a conical nose portion terminating in the cutting point. The cutting point may comprise a tip of hard cutting alloy affixed to the conical portion of the cutter bit. in some instances, the entire cutter bit may be made of hard cutting alloy, with or without a separate hard cutting tip. The other type of bit comprises a conical bit element intended to be removably affixed to an adapter. The adapter includes an elongated shank portion. In one form, the bit may comprise a hollow conical member, with or without a tip of hard cutting alloy. The adapter includes a conical nose portion at one end of the shank, configured to be received within the hollow cutter bit. In another form, the conical cutter bit may have an internal shank configured to be received in a perforation in the adapter.

Bits of these general types are especially useful for heavyduty applications wherein the bits have a greater service life and affect a better usage of hard alloy tips. In any of the cutting tools described above, the elongated shanks are adapted to be received in shank receiving perforations in mounting means. The shanks are of circular cross section and the shank receiving perforations are of such diameter as to permit rotation of the shanks therein. In use, the cutting tools will rotate about their long axes, the rotation being generated by the mutual reaction of the cutting tools and the material being cut. This rotation assures even wear of the cutting tools and produces a self-sharpening effect.

In connection with cutting tools of the type described above, means have to be provided for determining the gauge of the cutting tools. By this is meant that means must be provided to determine the depth to which a cutting tool shank will enter the shank receiving perforation in a mounting means. In prior art structures, a forward abutment means was normally provided on the shank of the cutting tool which would contact an abutment surface in association with the forward face of a mounting means. Often, the forward abutment means on the shank took the form of an annular shoulder. In some instances, the annular shoulder was provided with a tapering underside for engagement in a corresponding counter sink in the forward end of the shank receiving perforation in the mounting means.

Cutting tools of the type described, when used on heavyduty mining machines functioning continuously during the mining operation, are subjected to heavier and more continuous strains. The provision of the above-mentioned forward abutment means necessitated an abrupt change in diameter in the cutting tool shank at the juncture between that portion of the shank lying within the shank receiving perforation of the mounting means, and that portion lying outside of the shank receiving perforation.

It was further discovered that such changes in diameter in a cutting tool shank constituted stress-raisers, tending to concentrate the cutting strains and tending to cause failure of the shank at the position of a stress-raiser. This was found to be true whether the changes in diameter were toward a lesser or a greater diameter. It was further found that it was particularly undesirable to have stress-raising changes in diameter in that portion of a shank which was termed the critical zone." Since the diameter of the shank is slightly less than the diameter of the holding means perforation (so that the shank is freely rotatable therein), there will be a forwardmost and a rearwardmost area of contact between the lateral exterior surface of the shank and the corresponding interior surface of the holding means perforation. The critical zone of the shank comprises that portion thereof extending substantially from the above-mentioned rearwardmost area of contact to a point beyond and in the immediate vicinity of the above-mentioned forwardmost area of contact.

It is taught in US. Pat. No. 3,397,0l2 that the provision of a rear abutment surface on the cutting tool shank and an abutment surface in association with the shank receiving perforation of the mounting means enabled the use of a cutting tool being free of stress-raising diameter changes, particularly in the critical zone. Such a structure further permitted the use of novel and improved retaining means to prevent removal of the shank of the cutting tool from the shank receiving perforation of the mounting means. These structures have proven in the field to be characterized by a greater strength and a longer life than was obtainable with prior art cutting devices.

In US. Pat. No. 3,397,0l3 it is taught that the useful life of the parts can be appreciably extended and wear on the parts can be appreciably minimized by the provision of a male and female engagement between the abutment surface on the rear end of the cutting tool shank and the abutment surface in association with the shank receiving perforation of the mounting means. In this way, a greater area of contact between the cooperating abutment surfaces is achieved, thereby minimizing wear. The contact between the inside surface of the shank receiving perforation of the mounting means and the exterior surface of the shank of the cutting tool is more nearly a line contact, appreciably minimizing wear on both elements. The shank receiving perforation in the mounting means tends to maintain its proper diameter throughout its length. Wear at the rear end of the shank receiving perforation is particularly reduced, whereby the useful life of the shank retaining means is increased. Finally, the male-female engagement of the shank and mounting means abutment surfaces provides a pivot point about which the shank can rotate, thus further minimizing the departure from parallelism between the cutting tool shank and the shank receiving perforation of the mounting means. This additionally tends to reduce wear of these parts.

The present invention is concerned primarily with additional improvements in the abovedescribed assemblies.

SUMMARY OF THE INVENTlON The present invention is directed primarily to improvements in mounting means of the general type set forth in the abovementioned patents. The mounting means of the present invention are intended to be used with'cutting tools of the type comprising an elongated shank with cutting means at one end and an abutment surface at the other end.

The mounting means of the present invention comprise a body having a forward surface and a rearward surface and a shank receiving perforation extending therethrough from the forward surface to the rearward surface. The body is afiixed to a driven element of the mining machine. The driven element may comprise a chain block, a cutting wheel or a cutter arm. The driven element has, in association therewith, an abutment means providing an abutment surface spaced from the rear surface of the body and adapted to cooperate with the abutment surface on the cutting tool.

In one embodiment of the present invention, the mounting means comprises a lug affixed to a driven element. The lug has a forward extension with an abutment surface thereon, adapted to cooperate with the abutment surface on the cutting tool shank mounted in a similar lug positioned ahead of the first-mentioned lug. In another embodiment, the driven element will be provided with a stepped or toothed surface, the upper surface of each tooth bearing a body having a shank receiving perforation; the forward surface of each step or tooth comprising an abutment surface. In yet another embodiment, the driven element will have affixed thereto a body with a shank receiving perforation. Behind the body, an upstanding abutment means will be located which may be a separate means affixed to the driven element or which may comprise an integral, one-piece portion of the driven element. In a final embodiment, the driven element will have an upstanding portion with a deep V-shaped notch therein. A body with a shank receiving perforation will be affixed to one side of the V- shaped notch, the other side of the notch comprising the abutment surface.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a fragmentary side elevation of a driven element having a plurality of lugs afiixed thereto, each lug having a forward extension with an abutment surface thereon to cooperate with the abutment surface on the shank of the cutting tool in a lug located in front of the first-mentioned lug.

FIG. 2 is a plan view of the lug and cutting tool assembly of FIG. 1.

FIG. 3 is a fragmentary, elevational view, partly in cross section, of a driven element having a stepped or toothed configuration with a body having a shank receiving perforation mounted on the upper surface of each step or tooth, the forward surface of each step or tooth comprising an abutment surface.

FIG. 4 is a plan view of an assembly similar to FIG. 3, wherein the abutment surfaces on the driven element and the bodies having shank receiving perforations are oriented at various angularities.

FIG. 5 is a fragmentary elevational view of a driven means having affixed thereto a body with a shank receiving perforation and an abutment means providing an abutment surface.

FIG. 6 is an elevational view of a driven element having an upstanding portion with a deep V-shaped notch, a body with a shank receiving perforation affixed to one side of the notch, the other side of the notch comprising an abutment surface.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With respect to the present invention, the precise type and configuration of the cutting tool, the type of retaining means used and the configuration of the abutment surface on the cutting tool and on the driven element do not constitute limitations. Substantially any of the cutting tools, abutment surfaces and retaining means taught in the above-identified patents may be used in association with the mounting means described hereinafter.

In FIG. 1, a driven element is fragmentarily shown and is generally indicated at 1. While the driven element 1 may comprise a cutter arm or the like, for purposes of an exemplary showing it is illustratedas comprising a cutting wheel of the type well known in the art. The cutting wheel has a peripheral surface 2 to which a plurality of lugs are affixed by any suitable means such as welding or the like. One lug is generally indicated at 3. The lug has a body portion 4 having a forward surface 5 and a rearward surface 6. A shank receiving perforation 7 extends through the body 4 from the forward surface 5 to the rearward surface 6. The body portion 4 has a forward extension 8 with an abutment surface 9 thereon. A second lug, identical to that described, generally indicated at 3a. Like parts have been given like index numerals followed by a.

Yet another lug is fragmentarily illustrated in FIG. 1 and is generally indicated at 3b. This lug is identical to the lugs above described and like parts have been given like index numerals followed by b.

The lugs are located one behind the other, and it will be understood that lugs will be similarly arranged on the entire peripheral surface 2 of the cutting wheel I.

The lug 3 is illustrated as having a cutter bit mounted therein. The cutter bit is generally indicated at 10. For purpose of an exemplary showing, the cutter bit 10 is illustrated as being of the type having a shank ll of circular'cross section and an integral, tapered nose 12. The nose l2 terminates in a hard cutting tip 13. The rear end of the shank l 1 terminates in an abutment surface 14.

Again, for purposes of an exemplary showing, the cutter bit 10 is shown as having a retaining means comprising a split metal ring 15 located in an annular groove 16 in the shank II. The split metal ring 15 may be snapped into and out of the groove 16, as described in the above-mentioned patents. The outside diameter of the split metal ring 15 is greater than the diameter of the shank receiving perforation 7, so that when the ring is in position, the cutter bit 10 cannot be withdrawn from the shank receiving perforation 7.

The lug 3a is illustrated as having a cutter bit [00 mounted therein. This cutter bit is identical to that mounted in the lug 3, and like parts have been given like index numerals followed by a. Yet another identical curler bit is fragmentarily shown at [0b. The cutter bit 10b is mounted in a lug (not shown) positioned ahead of the lug 3a. Like parts of the cutter bit 10b have been given like index numerals followed by b."

From FIG. 1, and the above description, it will be seen that the forward abutment surface of a given lug is adapted to cooperate with the abutment surface on the cutting tool mounted in the lug immediately in front of the first-mentioned lug. Thus, lug abutment surfaces 90, 9 and 9b cooperate with shank abutment surfaces 14b, 14a and 14 respectively.

In the usual practice, lugs are affixed to the driven elements of mining machinery such as chains, wheels or cutter arms in such a way that they are oriented at different angularities to the driven elements. In this way, the cutting points of the various cutting tools will form a cut of sufficient width to permit the passage of the driven elements to the extent desired. Often, even the lugs of the center cutting bits may be oriented at a slight lateral angle to the direction of motion of the bit so as to increase the natural tendency of the bit to rotate during the cutting operation.

FIG. 2 is a plan view of the lug 3 of FIG. 1. It will be noted that the forward abutment surface 9 is an arcuate surface. The provision of an arcuate surface will enable the orientation of the lugs on the peripheral surface 2 at any desired angularity. Despite the angularity, the abutment surface on a cutting tool in a given lug will find an adequate cooperating abutment surface on the next lug behind. It will be understood by one skilled in the art that it would be within the scope of the invention to provide the surface 9 on each lug in the form of a planar surface having an appropriate angularity with respect to the adjacent lug. This would require, however, the provision of a plurality of lugs having abutment surfaces 9 oriented at a plurality of angularities.

FIG. 3 illustrates another embodiment of the present invention. A driven element is fragmentarily shown and generally indicated at 17. While the driven element will again be described as a cutting wheel, it will be understood that it could constitute any form of well-known mining machine driven element such as a cutter arm or the like.

In this instance, the entire periphery of the cutting wheel is provided with a plurality of steplike or toothlike configurations, three of which are fragmentarily shown at 18, 18a and 18b respectively. Each of the steplike configurations has an upper surface 19, 19a and 1% respectively and a forward surface 20, 20a and 20b respectively.

The upper surfaces 19, 19a and 19b are adapted to have body members or lugs afiixed thereto. Two such lugs are shown at 21 and 21a. The lug 21 has a forward surface 22, a rearward surface 23, and a shank receiving perforation 24. The lug 21a is identical, and like parts have been given like index numerals followed by "a."

While, as indicated above, the precise nature of the cutting tool does not constitute a limitation on the present invention, for purposes of an exemplary showing the lug 21 is illustrated as having a cutting tool (generally indicated at 25) mounted therein, the cutting tool being of the type comprising an adapter 26 and a conical cutter bit 27. The adapter has a shank 28 of circular cross section. The rearward end of the shank terminates in a flat abutment surface 29. The forward end of the shank has an integral, conical nose portion 30, tapering toward the forward end thereof. The nose 30 has a portion 31 of opposite taper which terminates at the juncture of the shank 28 and the nose 30. The cutter bit 27 may be made by forging, by upsetting, by a turning operation, as a screw machine product, by powdered metallurgy and in other ways not constituting a limitation on the present invention. Both the outer and inner surfaces of the cutter bit are conical and the bit may be provided with a tip 32 of hard cutting alloy. The lower portion 33 of the bit may be distorted at one or more places so that its diameter will be such as to require that the bit portion 33 be expanded in order to pass over the portion 31 of the adapter nose. This is most conveniently accomplished by placing the bit over the conical nose 30 of the bit adapter and driving the bit home by a hammer blow exerted through the use of a tool having an operating face softer than the substance of the hard cutting tip 32. Since the distortion of the lower end 33 of the bit is a resilient distortion, the bit will snap in place and be firmly held on the adapter 26.

Again, the means for retaining the adapter 26 in the shank receiving perforation 24 does not constitute a limitation on the present invention. For purposes of an exemplary showing, the end of the shank 28 is illustrated as having a transverse perforation 34 adapted to receive a roll pin 35 (as described in the above-mentioned patents). The ends of the roll pin 35 extend beyond the periphery of the shank 28 by a distance sufficient to prevent withdrawal of the shank from the shank receiving perforation 24.

Again, for purposes of exemplary illustration, the lug 21a is shown as having a bit in every way identical to the bit in FIG. 1. Like parts have been given like index numerals.

Irrespective of the type of cutting tool, its precise configuration and the retaining means used in association therewith, both of the cutting tools 10 and 25 have rear abutment surfaces 14 and 29 respectively. The forward surfaces 20, a and 20b of the toothlike or steplike portions of the cutting wheel are adapted to act as abutment surfaces cooperating with the abutment surfaces on the ends of adjacent cutting tools. Thus, the cutting tool abutment surface 14 cooperates with abutment surface 20a on the cutting wheel and cutting tool abutment surface 29 cooperates with wheel abutment surface 20.

FIG. 4 illustrates an assembly of the type described with respect to FIG. 3. A cutting wheel is fragmentarily shown and generally indicated at 36. Three of the steplike or toothlike configurations are shown at 37, 38 and 39. The steps each have an upper surface 37a, 38a and 39a respectively, and a forward or abutment surface 37b, 38b and 39b respectively. Three lugs, in every way similar to the lugs 21 and 21a of FIG. 3, are shown at 40, 41 and 42. The purpose of FIG. 4 is to illustrate, in an exemplary manner, the way in which the various lugs may be affixed about the periphery of the cutting wheel at varying angles to the direction of rotation (indicated by arrow A). Lug 41 is mounted on the surface 39a in such a way that a cutting tool (not shown) mounted therein will extend in the direction of arrow A. Consequently, the cutting wheel abutment surface 38b, adapted to cooperate with the abutment surface on the cutting tool, is oriented so as to be perpendicular to the cutting direction. Lugs 40 and 42, on the other hand, are affixed to the cutting wheel at opposite angularities to the cutting direction A. A cutting tool (not shown) mounted in lug 40 will extend beyond the edge 36a of the cutting wheel. Similarly, a cutting tool (not shown) mounted in the lug 42 will extend beyond the edge 36b of the cutting wheel. In order to assure proper alignment of the cutting tool abutment surfaces and the cutting wheel abutment surfaces the cutting wheel abutment surfaces 37b and 3% will be angled transverse the cutting wheel with respect to the cutting direction A. Such an arrangement will assure that the cut made by the cutting tools about the periphery of the cutting wheel will be of sufficient width to permit passage of the cutting wheel and its appurtenances.

FIG. 5 illustrates yet another embodiment of the present invention. A driven element of the mining machine is fragmentarily shown at 43. The driven element may comprise a chain block, a cutting wheel or a cutting arm. In this instance, a lug or body 44 is provided having a forward surface 45, a rearward surface 46 and a shank receiving perforation 47. The lug may be affixed to the driven element 43 by any suitable means including welding and the like.

Behind the lug or body 44 there is provided an abutment means 48. The abutment means may be a separated member affixed as by welding or the like to the driven element 43, or the abutment means 48 may be an integral, upstanding portion of the driven element. The abutment means 48 has an abutment surface 49 facing the rear surface 46 of the lug or body 44.

A cutter bit is illustrated as mounted in the shank receiving perforation 47 of the lug or body 44. Again, the cutter bit may be of any appropriate configuration. For purposes of an exemplary showing the cutter bit is illustrated as being the same as the cutter bit 10 in FIG. 1 and like parts have been given like index numerals.

When the lug or body 44 and the abutment means 48 are separate elements, to be affixed to the driven element as by welding or the like, it will be understood that they may be arranged at any desired angularity to the cutting direction. It is only necessary to assure that the body 44 and the abutment means 48 are properly aligned with respect to each other so that the abutment surface 49 will coact properly with the cutting tool abutment surface 14.

Another embodiment of the present invention is illustrated in FIG. 6. In this instance, for purposes of an exemplary showing, the driven element (generally indicated at 50) is shown in the form of a cutter chain block. It will be understood by one skilled in the art that the embodiment of FIG. 6 is not so limited and the construction shown therein may be applied to any type of driven element.

The block 50 has an upwardly extending body 51 having therein a deep V-shaped notch (generally indicated at 52). The V-shaped notch provides two surfaces 53 and 54. A second body 55 is affixed by welding or the like to the surface 53. The body 55 may have any suitable exterior configuration and presents a forward surface 56 and a rearward surface 57. For example, the body 55 may be made out of rod or bar stock of circular cross section. A shank receiving perforation 58 will be provided in the body 55.

A cutting tool (generally indicated at 59) is illustrated as being mounted in the shank receiving perforation 58. The cutting tool 59 is similar to those shown in FIGS. 1-3 and 5, and comprises a shank 60, an integral nose 61, a hard cutting tip 62 and a rear abutment surface 63.

In this instance, the cutting tool 59 is illustrated as having a retaining means similar to that described with respect to the cutting tool 25 of FIG. 3. The shank 60 has a transverse hold (not shown), into which a roll pin 64 is inserted.

While it will be understood that the surface 54 may itself constitute an abutment surface on the driven element 50 adapted to cooperate with the cutting tool abutment surface 63, for purposes of an exemplary showing the driven element 50 is illustrated as having a replaceable abutment surface of the type taught in the above-mentioned patents. Similar replaceable abutment surfaces may be applied to all of the embodiments of the present invention.

As shown, the body 51 is provided with a perforation 65 extending from the surface 54 through the body. The perforation 65 is coaxial with the shank receiving perforation 58 and of a lesser diameter. The replaceable abutment surface (generally indicated at 66) comprises an element 67 having an abutment surface 68 thereon. The element 67 is adapted to lie along the surface 54 and has a rearwardly extending lug 69 affixed thereto. The rearwardly extending lug 69 is adapted to be received in the perforation 65 and have a frictional engagement therein. When the surface 68 becomes worn, the replaceable abutment means 66 may be removed by blows to a suitable tool (not shown) inserted in the perforation 65 and located against the end of the lug 69.

In all of the embodiments above described, the shank receiving perforations will have a diameter such that the cutting tool shanks will be freely rotatable therein. In addition, the shank receiving perforations will be oriented in such a way that the cutting tool tips will lie above the highest part of the mounting means, and the axis of the cutter bit will lie at an angle of less than 90 to the direction of motion of the bit in the cutting operation so that the resultant cutting stresses will be sustained substantially in linewith the cutting tool axis.

In all of the above-described'embodiments, the abutment surface on the driven element and the abutment surface on the cutting tool may be configured to have a male-female engagement, as described in the above-mentioned US. Pat. No. 3,397,013. For purposes of an exemplary showing, such a male-female engagement is illustrated in dotted lines in FIG. 3.

In FIG. 3, a conical abutment surface 70 is shown in dotted lines on the shank 28 of the cutting tool 25. The abutment surface 20 on the cutting wheel is shown in dotted lines as having a cooperating conical depression 71.

In the same figure, the cutting tool 10 is shown in dotted lines as having a rear abutment surface 72 of rounded configuration. The abutment surface a on the cutting wheel is illustrated in dotted lines as having a rounded depression 73.

Modifications may be made in the invention without departing from the spirit of it.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A mounting means for the cutting tools of mining machines and the like of the type having an elongated shank of circular cross section, a hard cutting tip at one end and an abutment surface at the other end, said mounting means comprising a driven element of said mining machine and a plurality of bodies affixed to said driven element one behind the other, said driven element capable of driving said bodies in a cutting direction, each of said bodies having a forward surface, a rearward surface, and a shank receiving perforation extending through said body from said forward surface to said rearward surface, said shank receiving perforation being of such diameter as to permit free rotation of a cutting tool shank therein, said shank receiving perforation being of such length that the abutment end of said cutting tool extends beyond said rearward surface of said body, said driven element having a plurality of steps thereon, each of said steps comprising a first surface sloping upwardly and forwardly toward said cutting direction and a second surface sloping downwardly and forwardly toward said cutting direction, each of said bodies being mounted on one of said first surfaces with the rearward surface of said body being spaced from said adjacent second surface of the adjacent step, said last-mentioned second surface facing said last-mentioned rearward surface and presenting an abutment surface spaced therefrom and adapted to cooperate with said abutment surface on a cutting tool.

2. The structure claimed in claim I wherein said driven element comprises a cutting wheel of a mining machine.

3. The structure claimed in claim 1 wherein some at least of said bodies are so arranged on their respective first surfaces of said driven element as to have the axes of 4. A mounting means for the cutting tools of mining machines and the like of the type having an elongated shank of circular cross section, a hard cutting tip at one end and an abutment surface at the other end, the mounting means comprising a driven element of said mining machine and a body affixed to said driven element, said driven element capable of driving said body in a cutting direction, said body having a forward surface, a rearward surface, and a shank receiving perforation extending through said body from said forward surface to said rearward surface, and shank receiving perforation being of such diameter as to permit free rotation of a cutting tool shank therein, said shank receiving perforation being of such length that said abutment end of said cutting tool extends beyond said rearward surface of said body, said driven element having first and second surfaces forming a V-shaped notch, said body being affixed to said first surface with the axis of said shank receiving perforation parallel to said first surface and said rearward surface of said body being spaced from said second surface on said driven element, said second surface facing said rearward surface of said body and having thereon an abutment surface adapted to cooperate with said cutting tool abutment surface.

5. The structure claimed in claim 4 wherein said driven element comprises a chain block.

6. The structure claimed in claim 4 wherein said body is cylindrical in configuration, said body having an axial bore comprising said shank receiving perforation.

mg? UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,627,381 Dated December 1'4, 1971 Inve t r( Claude B. Krekeler It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 8, line 16 (line 3 of claim 3), the claim should be completed by adding the following: their shank receiving perforations lying at a plurality of transverse angularities to said cutting direction.

Signed and sealed this 20th day of February 1973.v

(SEAL) Attest:

EDWARD M. PLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

1. A mounting means for the cutting tools of mining machines and the like of the type having an elongated shank of circular cross section, a hard cutting tip at one end and an abutment surface at the other end, said mounting means comprising a driven element of said mining machine and a plurality of bodies affixed to said driven element one behind the other, said driven element capable of driving said bodies in a cutting direction, each of said bodies having a forward surface, a rearward surface, and a shank receiving perforation extending through said body from said forward surface to said rearward surface, said shank receiving perforation being of such diameter as to permit free rotation of a cutting tool shank therein, said shank receiving perforation being of such length that the abutment end of said cutting tool extends beyond said rearward surface of said body, said driven element having a plurality of steps thereon, each of said steps comprising a first surface sloping upwardly and forwardly toward said cutting direction and a second surface sloping downwardly and forwardly toward said cutting direction, each of said bodies being mounted on one of said first surfaces with the rearward surface of said body being spaced from said adjacent second surface of the adjacent step, said last-mentioned second surface facing said last-mentioned rearward surface and presenting an abutment surface spaced therefrom and adapted to cooperate with said abutment surface on a cutting tool.
 2. The structure claimed in claim 1 wherein said driven element comprises a cutting wheel of a mining machine.
 3. The structure claimed in claim 1 wherein some at least of said bodies are so arranged on their respective first surfaces of said driven element as to have the axes of their shank receiving perforations lying at a plurality of transverse angularities to said cutting direction.
 4. A mounting means for the cutting tools of mining machines and the like of the type having an elongated shank of circular cross section, a hard cutting tip at one end and an abutment surface at the other end, the mounting means comprising a driven element of said mining machine and a body affixed to said driven element, said driven element capable of driving said body in a cutting direction, said body having a forward surface, a rearward surface, and a shank receiving perforation extending through said body from said forward surface to said rearward surface, and shank receiving perforation being of such diameter as to permit free rotation of a cutting tool shank therein, said shank receiving perforation being of such length that said abutment end of said cutting tool extends beyond said rearward surface of said body, said driven element having first and second surfaces forming a V-shaped notch, said body being affixed to said first surface with the axis of said shank receiving perforation parallel to said first surface and said rearward surface of said body being spaced from said second surface on said driven element, said second surface facing said rearward surface of said body and having thereon an abutment surface adapted to cooperate with said cutting tool abutment surface.
 5. The structure claimed in claim 4 wherein said driven element comprises a chain block.
 6. The structure claimed in claim 4 wherein said body is cylindrical in configuration, said body having an axial bore comprising said shank receiving perforation. 